<template>
  <view>
    <my-search  @myclick="gotoSearch"></my-search>
      <view class="scroll-view-container">
        <!-- 左侧的滚动视图区域 -->
        <scroll-view class="left-scroll-view" scroll-y :style="{height: wh + 'px'}">
          <block v-for="(item, i) in cateList" :key="i">
            <view :class="['left-scroll-view-item', i === active ? 'active' : '']" @click="activeChanged(i)">{{item.cat_name}}</view>
          </block>
        </scroll-view>
        <!-- 右侧的滚动视图区域 -->
        <scroll-view class="right-scroll-view" scroll-y :style="{height: wh + 'px'}" :scroll-top="scrollTop">
          <view class="cate-lv2" v-for="(item2, i2) in cateLevel2" :key="i2">
            <!-- 二级数据列表 -->
              <view class="cate-lv2-title">/ {{item2.cat_name}} /</view>
              <!-- 动态渲染三级分类的列表数据 -->
                  <view class="cate-lv3-list">
                    <!-- 三级分类 Item 项 -->
                    <view class="cate-lv3-item" v-for="(item3, i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
                      <!-- 图片 -->
                      <image :src="item3.cat_icon"></image>
                      <!-- 文本 -->
                      <text>{{item3.cat_name}}</text>
                    </view>
                  </view>
          </view>
        </scroll-view>
      </view>
    </view>
</template>

<script>
  import badgeMix from '@/mixins/tabbar-badge.js'
  
  export default {
    // 将 badgeMix 混入到当前的页面中进行使用
    mixins: [badgeMix],
      data() {
        return {
          // 窗口的可用高度 = 屏幕高度 - navigationBar高度 - tabBar 高度
          wh: 0,
          cateList:[],
          cateLevel2:[],
          active:0,
          scrollTop:0
        };
      },
      onLoad() {
        // 获取当前系统的信息
        const sysInfo = uni.getSystemInfoSync()
        // 为 wh 窗口可用高度动态赋值
        this.wh = sysInfo.windowHeight - 50
        this.getCateList()
      },
      methods:{
        async getCateList(){
         const { data:res } = await uni.$http.get('/api/public/v1/categories')
         console.log(res);
         if(res.meta.status !== 200) return uni.$showMsg()
         this.cateList = res.message
         this.cateLevel2 = res.message[0].children
        },
        activeChanged(i){
          this.active = i
          // 为二级分类列表重新赋值
          this.cateLevel2 = this.cateList[i].children
          // 让 scrollTop 的值在 0 与 1 之间切换
          this.scrollTop = this.scrollTop ? 0 : 1
        },
        // 点击三级分类项跳转到商品列表页面
        gotoGoodsList(item3) {
          uni.navigateTo({
            url: '/subpkg/goods_list/goods_list?cid=' + item3.cat_id
          })
        },
        // 跳转到搜索页面函数
        gotoSearch() {
             uni.navigateTo({
               url: '/subpkg/search/search'
             })
           }
      }
    }
</script>

<style lang="scss">
.scroll-view-container {
  display: flex;

  .left-scroll-view {
    width: 120px;

    .left-scroll-view-item {
      line-height: 60px;
      background-color: #f7f7f7;
      text-align: center;
      font-size: 12px;

      // 激活项的样式
      &.active {
        background-color: #ffffff;
        position: relative;

        // 渲染激活项左侧的红色指示边线
        &::before {
          content: ' ';
          display: block;
          width: 3px;
          height: 30px;
          background-color: #c00000;
          position: absolute;
          left: 0;
          top: 50%;
          transform: translateY(-50%);
        }
      }
    }
    
  }
  .cate-lv2-title {
    font-size: 12px;
    font-weight: bold;
    text-align: center;
    padding: 15px 0;
  }
  .cate-lv3-list {
    display: flex;
    flex-wrap: wrap;
  
    .cate-lv3-item {
      width: 33.33%;
      margin-bottom: 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
  
      image {
        width: 60px;
        height: 60px;
      }
  
      text {
        font-size: 12px;
      }
    }
  }
}
</style>
